Pump



Oct. 11, 1932. H. s. LEE 1,881,723

PUMP

Filed July 15. 1929 2 sheets-sheet 2 IN VEN TOR.

/arfy Lee MMM A TTORNE Y.

Patented Oct. l1, 1932 .UNITED/f STATES PATENT OFFICE .r HARRY S. LEE.OF DETROIT, MICHIGAN PUMP applicati@ mea my 15, 192s. serial No.378,287.

handlinga liquid containing an abrasive subp stance, such as sand,cement or the like.

Pumps of this nature are used in cement manufacturing plants for pumpingthe slurry, which is a wet mixture containing cement. The cement, ofcourse, is extremely abrasive, and it has been found that the packingbox, or stuffing box of the pump very rapidly becomes useless or wornout once the cement attains access thereto, inasmuch as the cement Wearsaway the packing material. It follows that the pump can only be used fora relatively short While, until it has to be torn down and a newstuffing box placed therein. It has been proposed to provide theseslurry umps with a water seal instead of a dry stu ng box, but this isobjectionable because it adds a material amount of water to the mixture,thus requiring more energy and the use of more coal or other fuel to drythe mixture.

One of the reasons why the stuffing box of a slurry pump is so shortlived is that the impeller shaft vibrates in its operation, and as aresult, there is a wearing away of the packing material, or in anyevent, the packing material is somewhat loosened on the shaft, thusallowing the abrasive mixture to enter, and once the abrasive mixtureattains access to the packing material, it is a matter of a very shorttime until the stuiing box is completely destroyed as such.

This invention contemplates an arrangement of a stuffing box and otherassociated parts of the pump, wherein the abrasive mixture will beprevented from having access to the packing material for a relativelylong period of time, and with this in view, an arrangement is providedwherein the stuiing box is so mounted with relation to the shaft thatthe shaft vibrations will not cause a wearing away or mis-shaping of thepacking material. More speciically, the invention contemplates theprovision of a floating, dry,

' stuffing box so mounted as to move with a vibrating shaft somewhat ina oating manner as regards the pump housing. Furthermore, the inventioncontemplates the employment of an additional rotary pum -like memberwhich is arranged so as to e ect a pumping action, which tends to drawthe slurry away from the packing box.

In the accompanying drawings:

Fig. l is a sectional view taken through a pump constructed inaccordance with the invention, showing the mounting of the stuifing boxand various details of the structure.

Fig. 2 is a composite section and side elevational view of the pump,empellel Fig. 3 is a yview of one of the head plates i of the pump.

Fig. 4 is an enlarged section taken on line 4-4 of Fig. 3.

Fig. 5 is a side view of one of the spring retaining devices employed inconjunctionA with a spring for effecting pressure on the packingmaterial.

Fig. 6 is a view of a clamping ring member employed in the mounting ofthe floating stuffing box.

Fig. 7 is a view illustrating a sealing collar used in the constructionfor effecting a flow tendency which keeps the. slurry away from thestuffing box.

In the drawings there is shown a shaft 1, journaled in bearing 2 incasing or housing 3, and this shaft is driven as by means of a suitablemotor (not shown). The shaft may be connected to the shaft of anelectric motor, or it may be driven by employing a belt and pulleywheel, or the like. On the end of this shaft there is mounted theimpeller 5 of a pump, so that the shaft in its rotation, rotates theimpeller. The impeller shown is one of the type having impeller blades,or vanes 6, confined between spaced radial walls 7 and 8. Outside of thewalls are vanes 9 and 10 which may be described as being continuationsof the impeller blades 6. These function in a manner as will be laterset forth.

The pump housing, or casing, comprises an annular member 15, havingsecured thereto, head or closure members 16 and 17. The invlet for thematerial to be pumped is shown. at

' ing assembly and disassembly of the parts,

is at 19. The impeller works between liner discs 20 and 21 which arereplaceable, :and which are preferabl ,provided with a plurality of lugs22. ese lugsl 22 may of soft metal cast directly onto the hard hnerplate and machined to fit the member 15 as shown in Fig. 1. Thisarrangement ma es it unnecessary to machine the liner plates as a whole.The head member 16 and liner plate 21 have a central aperture whichprovides. for thevinlet, while the liner plate 20 relatively closelyhugs the hub portion of the impeller, and the closure plate 17 is shapedin such -manner that the packing box can be disposed to seal the pointwhere the shaft passes through the closure member 17.

The stuiiing box comprises .packing 25, which i-s disposed over theshaft and which is confined within a sleeve 26. This sleeve has a iange27 which frictionally engages a sealing collar 28, the sealing collarbeing mounted on the shaft to rotate therewith, and the frictionalengagement takingv place at the point 29. This sealing collar isprovided with vanes30 so that in its rotation, it efects a umping actionaway from this point of frictional contact. The sleeve 26 may also berecessed for the reception of a packing ring 31, which frictionallyenga-ges the sealing collar and aids in the seal at this point. p

The packing 25 is confined at one end by an internal shoulder 32 on thesleeve 26, `and at the other end by a collar member 33. This collar isslidable longitudinally of the shaft, and is backed up by `a coil spri34. The coil spring 34 may be in turn bac ed up by any suitablestationary part, as for example, the supporting member 35 which connectsthe pump housing with the shaft housing. However, there is preferablyprovided, packing 36 for retaining lubricant for the bearing 2, and thespring 34 may advantageously be placed between collar 33 and a similarcollar 37, which backs up against the packing; 36. These two collars 33and 37 may be provided with apertured ears 38, through whichscrewthreaded bolts 39 extend. By employing screw-threaded nuts on thesebolts, spring 34 may be held in a compressed manner durand these boltsor studs may be screwed into the base portion 35 during operation toinsure that these collars do not rotate.

The stuffing box, which includes the packing substance 25, is floatedupon the shaft,

tures in the member 17, therubber rings, and the metallic rings 41.These bolts are tightened down so as to make a sealed connection at thispoint.

These rubber rings are likewise sealed to the sleeve 26, andaccordingly, the rubber rin are bent so as to take substantially an L sape in cross section. Clamps 45 having ears 46 are placed over therubber rings where they lie drawn tig tly into position b the means ofsuitable bolts or screws 47. T e rubber rings upon the packing materialin the stuiing box is ruined in a very short time. Moreover, when'thepump is stopped, the material in the conduits disposed at an elevationhigher than the pump, flows by action of gravity into the pump andcompletely lills the same against the sleeve 26, and then are oftheshaft. Some so that the abrasive material 1s in close prox-A imity tothe stuing box; this makes it very essential that the stuffing box beperfect in order to allow no abrasive material to enter the same.

It will be noted that in accordance with this invention, the packingmaterial 25 is floating; that is to say, it is not bound tightly to any,part of the pump housing or other stationary part, but mounted so as tobe freely movable with the shaft. In other words, the pacln'ng 25 isfree to vibrate bodily with the shaft, at whichtime the rubber rings 40flex', thus permitting this action. Accordingly, the vibrations in theshaft do not pound against the `packing in such manner as to causeimperfections in it, as the packing rides with the shaft so to speak.

In the operation of the pump, the vanes 9 and 10 act to set up aVpumping action, thus preventing an accumulation of the material handledoutside of the impeller. Also, the vanes 30 on the sealing collar l28effect a pumping. action in the nature of a suction away from thecontact point 29 and the packing so as to tend to keep the materialhandled away from these parts. It will be noted that should the pump bestopped that the material handled, having a sulicient head outside thepump, will flow in between the impeller and the liner plate 20, thenthrough space 50, where it is stopped from further flowing by thestuilng box. When the pump is started, the blades 9 draw this materialout away from the stulling box, while the blades 30 tend to keep thesame away from the stuing box. If, however, there should be a defect inthe packing material, as may be caused by shaft vibrations asheretofore, the abrasive substance creeps into the same, and then, whenthe pump is started, this abrasive substance rapidly destroys thesealing action of the stuilng'box. v

The contact 29 may be lubricated by means of an oil cup, or othersimilar .lubricating device 51, communicating through pi 52 and channel53 in the sleeve 26 to this ring. It is advantageous to refer to a umpconstructed in accordance with this mvention, as a slurrypump for use incement handling, but of course, the invention is a plica-4 vble to pumpsfor all kinds of uses, as or example, the pumping of water carrying sandor the like, orA for pumps used any place where there is one or moreelements in the water or other Huid handled, which is liable to attackthe packing material.

I claim:

1. In a pump, a housin an impeller, a shaft upon which. the impe ler ismounted, a stuffing box comprisin a collar, packing material confinedwithin t e collar and engaging the shaft, flexible means connecting thecollar and housing, and a sealing disc mounted to rotate with the shaftand having frictional engagement with the collar inside the pumphousing. v

2. In a pump, a housin an impeller, a shaft upon which the impe er ismounted, a stuing box comprisingla collar, packing material confinedwlthin t e collar and engaging the shaft, flexible means connecting thecollar and housing, and a sealing disc mounted to rotate with the shaftand having frictional engagement with the collar inside the pump housmg,and vanes. on the'sealing disc arranged to effect a pumping action awayfrom the point of frict1ona1 contact during pump operation. l

In testimony whereof I aix my si ature.

HARRY S. E.

